By the time you add transportation and Federalization to the $5000 price tag you are at least to $15,000 US
If you are talking 850i that is around the right price for an Average '91-'92
A late model Sport version-- '96 or '97 might be worth considering but those are in the Mid $20k range now so unless it is perfect and un-altered that is a big question mark.
One of the other problems with importing is that you may end up waiting for a Year or so to actually get the car. Takes 8 to 12 weeks to actually do everything on the car but then you have to wait for the paperwork to be approved